Triphenylmethane dyestuff

ABSTRACT

A method for sanitizing flush toilets wherein a sanitizing agent and a triphenylmethane dyestuff are dispensed into the toilet flush water. The dyestuff is resistant to attack by the sanitizing and therefore provides an aesthetically pleasing color to the water remaining in the bowl during the time period between flushes.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of our copending application Ser. No.560,000, filed Dec. 9, 1983, and now U.S. Pat. No. 4,536,368.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to the automatic sanitizing of flushtoilets by means of dispensing certain water-soluble triphenylmethanedyestuffs and a sanitizing agent into the toilet bowl with each flush.The dyestuff is resistant to attack by the sanitizing agent and thus,provides color to the bowl water during the time period that the waterremains in the bowl between flushes.

(b) Information Disclosure Statement

Automatically dispensed toilet bowl cleaning and/or sanitizing systemswhich contain colorants to provide a visual signal to the user that thesanitizing product is being dispensed are well known. There are twogeneral types of these sanitizing systems available. One of thesesystems has a visual signal which is transitory, that is, the sanitizingsolution in the toilet bowl retains its colored appearance for only abrief amount of time. The other system, and one in which this inventionfinds its utility, is the system wherein the sanitizing solution in thetoilet bowl is intended to show persistent color until the next flush.

U.S. Pat. No. 3,504,384, which issued Apr. 7, 1970, discloses that thedyestuff known as Disulfide Blue VN150 can be incorporated intosurfactant components contained within a dual compartment dispenser forautomatically dispensing a hypochlorite solution and a surfactantsolution into the toilet bowl during flushing. This dye, which isbelieved to be Disulphine Blue VN150 (Color Index 42045) having theformula ##STR1## has been found to be resistant to oxidation to acolorless state by hypochlorite. But, solutions of this dye have atendency to change from a blue shade to a reddish-purple shade uponprolonged contact with hypochlorite.

U.S. Pat. No. 4,200,606, which issued Apr. 29, 1980, discloses a methodof treating a flush toilet, from a dual compartment dispenser forautomatically dispensing, with a hypochlorite sanitizing solution and asurfactant solution each time the toilet is flushed. A persistent coloris purportedly maintained in the bowl water by incorporating either FD&CBlue No. 1 having the formula ##STR2## or FD&C Green No. 3 having theformula ##STR3## into the surfactant solution.

U.S. Pat. No. 4,248,827, which issued Feb. 3, 1981, discloses a methodof treating a flush toilet each time it is flushed with abromide-catalyzed hypochlorite sanitizing solution and a surfactantsolution from a dual compartment dispenser for automatically dispensingthe solution. A transitory visual signal is provided to indicate theactivity of the sanitizing agent in the bowl by incorporating a dyeselected from the group of those identified by the Color Index numbers24401; 42040; 63010; 42085; 42675; and those having Color Index namesBasic Blue 80, Reactive Blue 17 and Acid Blue 182 into the surfactantsolution.

U.S. Pat. No. 3,545,014, which issued Dec. 8, 1970, discloses anautomatic sanitizer for flush toilets which contains a blue dye known asAcid Blue 9 (Color Index 42090) stated to impart a blue color to thewater in the bowl.

The most common sanitizing agent used in automatic toilet bowlsanitizers is a chemical compound which will generate hypochlorite ionin water. The hypochlorite ion is a strong oxidizing agent which makesit highly effective in bleaching stains, breaking down and removingsoils and killing microorganisms, thereby providing effective sanitizingaction to the toilet bowl. Although highly effective in bleachingstains, removing soil and killing microorganisms thereby providingeffective sanitizing action in the toilet bowl, hypochlorite ion willalso operate to bleach or oxidize any dye which is utilized as acolorant in the automatic toilet bowl sanitizers. In any toilet bowlsanitizing system which is designed to provide a persistent visualsignal between flushes, which period is often up to six to eight hoursor longer, any such system requires a dye which is resistant to attackby oxidizing agents such as hypochlorite and which will not be bleachedto a colorless state or oxidized to a different and aestheticallydispleasing shade or color. Currently known automatic toilet bowlsanitizers have been only partially successful in this regard andaccordingly there is a need for an automatic toilet bowl sanitizingsystem which provides a stable visual color signal which persists forbetween six to eight hours between flushings.

SUMMARY OF THE INVENTION

It has now unexpectedly been found that certain triphenylmethanedyestuffs have superior resistance to attack by oxidizing agents, forexample, hypochlorite and remain colored in the presence thereof forabout eight hours. The present invention provides a method of sanitizinga toilet bowl wherein a sanitizing agent, a surfaceactive agent and awater-soluble triphenylmethane dyestuff, which is resistant to attack bythe sanitizing agent, are automatically dispensed to the toilet bowlduring flushing. The water in the bowl at the end of the flush, whichremains in the bowl during the widely-varying time intervals betweenflushes, retains a persistent color with no shade or color shift becauseof the dyestuff's resistance to attack by the sanitizing agent.

In its chief aspect, the invention relates to a method of providing avisual color which persists in the toilet bowl water between flushes,that is, the color is resistant to bleaching by the sanitizing agent toa colorless state or oxidation to a different shade or color betweenflushes.

DETAILED DESCRIPTION OF THE INVENTION INCLUSIVE OF THE PREFERREDEMBODIMENTS

More specifically, this invention relates to a method of treating aflush toilet which comprises a flush tank and bowl, with a sanitizingagent each time the toilet is flushed and providing a persistent colorto the bowl water between flushes, said method comprising the step ofdispensing into the flush water an aqueous solution which contains (A) asanitizing agent, and (B) a triphenylmethane dyestuff selected from thegroup having the formula ##STR4## in which R represents benzyloptionally substituted in the benzene ring by SO₃ M in which Mrepresents an alkali metal cation, an ammonium ion or an alkaline earthmetal cation; R¹ represents a non-tertiary C₁ to C₄ alkyl; and Xrepresents hydrogen or hydroxy.

In a particular embodiment, the invention sought to be patented residesin a method of treating a flush toilet which comprises a flush tank andbowl, with a sanitizing agent each time the toilet is flushed andproviding a persistent color to the bowl water between flushes, saidmethod comprising the step of dispensing from separate dispensing means,into the flush water; (A) an aqueous solution of a sanitizing agent, and(B) a solution of a triphenylmethane dyestuff having Formula Ihereinbelow.

Within the ambit of the particular embodiment of the invention is themethod of treating a flush toilet wherein solution B contains atriphenylmethane dyestuff having the formula ##STR5## in which M and Xhave the same respective meanings given in Formula I.

A preferred sanitizing agent for use in the first particular embodimentis a sanitizing agent which produces hypochlorite ions in aqueoussolution.

In a second aspect, the invention sought to be patented resides in thenovel triphenylmethane dyestuffs of Formula II.

As used herein the term "non-tertiary C₁ to C₄ alkyl" denotes saturatedmonovalent straight or branched aliphatic hydrocarbon radicals includingmethyl, ethyl, propyl, isopropyl, butyl, isobutyl and the like.

As used herein the term "alkali metal cation" includes lithium, sodiumand potassium cations.

As used herein the term "alkaline earth metal cation" includes magnesiumand calcium cations.

The sanitizing agent which can be used in the practice of the presentinvention is any compound which will effectively clean and/or sterilizethe bowl of the toilet. The preferred sanitizing agents which can beused, and to which the colorant is resistant to attack, are compoundswhich exhibit germicidal or disinfectant properties and which haveoxidizing characteristics, that is, are ones which generate oxygen orhypochlorite ion in an aqueous solution. Compounds included within thisgroup which generate oxygen are the alkali metal and alkaline earthmetal salts of the peroxy acids such as perborates, percarbonates,peroxides and persulfates.

Compounds included within the group which generate hypochlorite ion inaqueous solution are the alkali and alkaline earth metal hypochlorites,hypochlorite addition products, chloramines, chlorimines andchloramides. Specific examples of this type of compound are: sodiumhypochlorite, potassium hypochlorite, lithium hypochlorite, calciumhypochlorite, calcium hypochlorite dihydrate, monobasic calciumhypochlorite, dibasic magnesium hypochlorite, chlorinated trisodiumphosphate dodecahydrate, potassium dichloroisocyanurate, sodiumdichlorocyanurate dihydrate, 1,3-dichloro-5,5-dimethylhydantoin,N-chlorosulfamide, Chloramine T, Dichloramine T, Chloramine B andDichloramine B. Also, free acids such as trichloroisocyanuric acid maybe used as a source of hypochlorite. The hypochlorite ion generatingcompounds are particularly preferred as sanitizing agents in theautomatic toilet bowl cleaners because they are relatively inexpensiveand exhibit a high degree of sanitizing strength per unit weight. Theamount of oxidizing agent such as, hypochlorite-providing compound,dispensed into the toilet by the so-called automatic bowl cleaner mayvary, but it is preferred that the amount released be sufficient toprovide from approximately 0.5 parts per million to approximately twentyparts per million of available chlorine or the equivalent thereof in thebowl water after completion of the flush.

Another effective sanitizing agent is oxalic acid.

Essential to the method of the instant invention is the use of awater-soluble, bleach resistant dye of Formula I which is sufficientlyresistant to oxidation that the solution of the dye in the toilet bowlwill not be oxidized to a different shade or color or to a colorlessstate by the oxidizing agent in the bowl for a time period of from sixhours to approximately eight hours, typically the maximum time intervalbetween flushes in the average household.

The dyes of Formula I are not completely stable to attack by theoxidizing agent; however, they are sufficiently resistant to attack toadequately serve as colorants for use in automatic toilet bowl cleaners.When there is a long time interval between flushes, there will be somefading of the color in the bowl water due to the slow attack by theoxidizing agent on the dye, but the water will not change color orshade, nor will it become colorless.

The amount of dye which is dispensed into the water of the toilet bowlis dependent on the color intensity desired and the amount of sanitizingagent dispensed by the automatic cleaner. In general, the amount of dyedispensed by the automatic cleaners will vary between approximately 0.05parts per million to approximately 10 parts per million in the water ofthe toilet bowl after the flushing is completed.

The triphenylmethane dyes of Formula I are readily prepared byprocedures well known in the dyestuff art. General methods for thepreparation of triphenylmethane dyestuffs from benzaldehydes andderivatives of aniline are taught in (a) FIAT Final Report No. 1313 and(b) PB Report 85172, pages 351-352.

Two of the preferred triphenylmethane dyestuffs of Formula I which areuseful in the present invention have the formulas ##STR6##

Surface active agents are usually added to the automatic sanitizersbecause these agents enhance the sanitizing performance by breaking upand emulsifying the soils present in the bowl, and further, the sudsingaction caused by these agents is aesthetically desirable.

The surface active agents are generally combined with a dyestuff ofFormula I and an inorganic salt which may also serve as a sequesteringagent or a pH control agent but, in any event, the inorganic salt aidsin dissolving the dye and the surface active agent. Optionally, aperfume may be added to this composition to provide a pleasant smell tothe area surrounding the toilet and also to help mask the hypochloriteodor of the hypochlorite-type of sanitizing agent. The compositionscontaining the dye of Formula I, the surface active agent and otheroptional components are generally prepared in the form of a cake whichis conveniently placed into one of the compartments of the dispensersdesigned to receive said cake of solid material. The cake can beprepared by pouring a melt of the composition into a mold andsolidifying the composition by cooling. Alternatively, the cakes can beprepared by extrusion or hydraulic stamping.

Surface active agents operable in compositions suitable for use inpracticing the present invention can be selected from the broad groupsknown as nonionic and anionic agents, ampholytic, zwitterionic andcationic surface active agents. One group of nonionic surface agentswhich can be utilized in the present invention is the alkylene oxidecondensates which are broadly defined as compounds produced by thecondensation of alkylene oxide groups (hydrophilic in nature) with anorganic hydrophobic compound. One example of such alkylene oxidecondensates are the products of aliphatic alcohols with ethylene oxide.The aliphatic alcohol generally has an alkyl chain which can be eitherstraight or branched and contains from about eight to about twenty-twocarbon atoms. An example of ethoxylated alcohols include thecondensation of ethylene oxide with tridecanol. An example of acommercially available nonionic surface active agent of this type isEmulphogene® TB-970 (GAF Corp.). Other products of varying carbon chainlength of the aliphatic alcohols and the number of moles of ethyleneoxide per mole of alcohol can be used. Other examples of commerciallyavailable nonionic surface active agents are Neodol® 25-9 (ShellChemical Co.) and Tergitol® 15-S-12 (Union Carbide Corp.). Othernonionic surface active agents which can be used in the presentinvention include the polyethylene oxide condensates of alkyl phenols;the condensation products of ethylene oxide with the product resultingfrom the reaction of propylene oxide and ethylene diamine; the ammonia,monoethanol and diethanol amides of fatty acids having an acyl moiety offrom about 8 to about 18 carbon atoms; and the semi-polar nonionicsurface active agents, for example, amine oxides, phosphine oxides andsulfoxides. Cationic surface active agents which are useful in thepresent invention are the quaternary ammonium compounds, for example,coconut dimethyl benzyl ammonium chloride. Examples of anionic surfaceactive agents are the water-soluble alkali metal salts of organicsulfonic acid reaction products such as the sodium or potassium salts ofsulfonated C₈ to C₁₈ alcohols and glyceride sulfonates.

The dispensing means which operate to dispense the sanitizing agent anddye-surfactant can be either a single dispensing or dual dispensingtype. In the dual dispensing type, the sanitizing agent and thedye-surfactant are dispensed from separate containers. Such devices areknown in the art, for example, as described in U.S. Pat. Nos. 3,504,384;4,200,606; 4,248,827; 4,249,274; and 4,353,866. There are severalcommercial automatic toilet bowl sanitizers on the market which are dualdispensing devices.

The dispensing means which operate to dispense a single solutioncontaining the sanitizing agent, dye and surfactant is a singledispenser. Such devices are known in the art, for example, as describedin U.S. Pat. Nos. 3,698,021; 3,604,020; 4,305,162; and 4,375,109. Thereare numerous commercial automatic toilet bowl sanitizers on the marketwhich are single dispensing devices.

The longevity of the dyestuff color in the sanitizing solution wasmeasured by simulating the conditions which exist in the toilet bowlafter the flushing cycle was completed when an automatic toilet bowlsanitizer was used. Solutions were prepared which contained 2.5 partsper million of dyestuff, 40.0 parts per million of a surface activeagent and 40.0 parts per million of sodium sulfate. After an initialvisible spectrum reading was taken, sufficient sodium hypochloritesolution or trichloroisocyanuric acid solution equal to 10.0 parts permillion of available free chlorine was added to the dyestuff solutionand spectrophotometer readings were taken automatically at specifiedpre-set time intervals depending on the dyestuff tested and thesanitizing agent employed. The dyestuffs of this invention were comparedwith FD&C Blue No. 1 and FD&C Green No. 3, the dyestuffs disclosed inU.S. Pat. No. 4,200,606, for the length of time the color persisted inthe simulated bowl water.

A simple qualitative test for the persistence of the dyestuffs ofFormula I in the presence of a sanitizing agent was carried out bydissolving the dyestuff in distilled water and adding sufficientdyestuff solution to one liter of distilled water thereby adjusting theresulting solution to the same visual strength as a solution of FD&CBlue No. 1. One such solution served as a control and another wastreated with sufficient sanitizing agent to give a concentration of 10.0parts per million in the sanitizing solution. The persistence of colorin the presence of sanitizing agent was determined visually bycomparison with the control. In testing for the longevity of thedyestuff color in the presence of hypochlorite-ion-generating sanitizingagents, three solutions were prepared in this manner, one a control, andthe remaining two solutions were tested with sanitizing agents. One wastested with a solution of trichloroisocyanuric acid, and the second withsodium hypochlorite solution. The amount of hypochloriteion-generatingsanitizing agent was added to 10.0 parts per million of availablechlorine in the dilute dyestuff solution. The amount of dyestuffremaining in the solution was visually observed and compared to thecontrol.

In order to carry out direct use tests, the dual dispensing devices forthe dye-containing surface active agent cake and the sanitizing agentcake were prepared to simulate commercially available dispensers. Thus,a commercial cake of trichloroisocyanurate was used in conjunction witha prepared surface-active agent cake containing a dyestuffs of FormulaI. The dual dispenser device was then tested in a flush toilet byinserting it into the tank. The persistence of the color of the bowlwater and staining effects were observed after several flushes withintermittent periods of standing between flushes.

In order to carry out direct use tests, the dual dispensing devices forthe dye-containing surface active agent cake and the sanitizing agentcake were prepared to simulate commercially-available dispensers. Thus,a commercial cake of trichloroisocyanurate was used in conjunction witha prepared surface-active cake containing a dyestuff of Formula I. Thedual dispenser device was then tested in a flush toilet by inserting itinto the tank. The persistence of the color of the bowl water andstaining effects were observed after several flushes with intermittentperiods of standing between flushes.

The persistence of the triphenylmethane dyestuffs of Formula I in thepresence of oxidizing agents and, in particular, in the presence ofhypochlorite was compared with that of the prior art triarylmethanedyestuffs, namely, FD&C Blue No. 1 (C.I. 42090) and FD&C Green No. 3(C.I. 42053) under conditions which simulate those existing in a toiletbowl after the flushing cycle is completed as well as in the actualtoilet bowl tests. The procedures employed are described in thecomparative examples.

PREPARATIVE EXAMPLE I

With stirring, 50.0 g of concentrated sulfuric acid and 348.6 g of 83.6percent N-ethyl-N-benzylaniline sulfonic acid were added to a mixture of164.0 g of the disodium salt of 2,4-disulfobenzaldehyde and 500.0 ml ofwater. The reaction mixture was maintained at reflux temperature forapproximately twenty-four hours and cooled to obtain a solution of{(2,4-disulfophenyl)-bis[N-ethyl-N-(3-sulfobenzyl)aminophenyl]}methane.

B. To the solution from part A above, there was added 570.0 ml of waterand 55.2 g of oxalic acid dihydrate and the resulting solution wasstirred approximately thirty minutes. To the solution, there was addeddropwise over approximately twenty minutes, 63.2 g of 70 percent sodiumdichromate at ambient temperature. The temperature gradually rose toapproximately 37° C. After approximately fifteen minutes, the reactionmixture was heated to approximately 70° C. and maintained forapproximately thirty minutes before cooling to ambient temperature.After setting overnight at ambient temperature, the reaction mixture washeated to approximately 70° C. and maintained for approximately onehour. Sufficient 10 percent sodium hydroxide was added slowly to thereaction mixture to set the pH at 7.0 and the resulting mixture wasmaintained at approximately 70° C. for approximately one hour. Then,47.2 g of calcium chloride and 84.0 g of barium chloride dihydrate wereadded to the reaction mixture while maintaining a pH between 6.5 and 7.0by adding 50 percent sodium hydroxide, as needed. The resulting mixturewas filtered and the filtercake washed with two 250.0 ml portions ofwater. The clear blue filtrate and wash was combined and spray dried toobtain 496.3 g of dark blue solid containing the dyestuff ##STR7## Thevisible spectrum of a water solution of the blue solid had a significantadsorption at 639 millimicrons.

PREPARATIVE EXAMPLE II

A. A mixture of 348.6 g of 83.6 percent N-ethyl-N-benzylaniline sulfonicacid, 500.0 ml of water, 5.5 ml of concentrated sulfuric acid and 52.7 gof 95 percent 3-hydroxybenzaldehyde was stirred at reflux temperatureunder a nitrogen atmosphere for approximately 22 hours. Then, 500.0 mlof water was added slowly to the reaction mixture and it was cooled toambient temperature. The supernatant liquid was poured from theresultant hard mass of solid. To the solid, there was added 1.0 liter ofwater and 55.0 ml of 50 percent aqueous sodium hydroxide. The resultingmixture was warmed gradually and stirred manually until all of the soliddissolved. The resulting alkaline solution was added dropwise withstirring to a solution of 90.0 ml of concentrated hydrochloric acid and3.0 liters of water. The pale green solid which formed was collected byfiltration, washed twice each time with 500.0 ml of water, and dried toobtain 308.0 g of{bis[4-N-ethyl-N-(3-sulfobenzyl)aminophenyl]-(3-hydroxyphenyl)} methane,a pale green solid which melted over the range of 260° to 270° C.

B. With stirring, 35.0 g of the product from Part A above was added insmall portions over approximately three hours to 150.0 g of 20 percentoleum while maintaining a temperature lower than 55° C. The reactionmixture was heated at approximately 70° C. for one hour and at atemperature between 75° and 85° C. for approximately four hours. Thereaction mixture was poured slowly with stirring into 500.0 ml of 10percent aqueous sodium sulfate solution. A brown tar-like mass resultedwhich settled to the bottom. The aqueous layer was decanted and setaside while the tar-like mass was dissolved in 50.0 ml of hot water. Tothe decanted water layer, there was added slowly 100.0 ml of 50 percentaqueous sodium hydroxide while maintaining a temperature below 30° C. Atar-like mass settled from the solution and was isolated by decantingand discarding the supernatant water layer. This second tar-like masswas dissolved also in 50.0 ml of hot water and the two solutionscontaining the dissolved tar-like solids were combined and diluted withan additional 70.0 ml of water. The pH of the aqueous solution wasadjusted slowly from 1.1 to 3.9 by adding dropwise 50 percent aqueoussodium hydroxide. With stirring, 7.0 g of oxalic acid and 8.0 g of 70percent aqueous sodium dichromate solution were added to the solution.The resulting mixture was heated to approximately 70° C. and the pHadjusted to 7.0 with the gradual addition of 50 percent aqueous sodiumhydroxide. The temperature was maintained at approximately 70° C. for anadditional hour. The resulting green solution was filtered throughdiatomateous earth to remove a trace of insolubles to obtain 258.0 g ofgreen solution. The solution was spray dried to obtain 50.1 g of solidswhich contain the dyestuff having the structure ##STR8## The visiblespectrum of a sample of the solid dissolved in water exhibited a maximumat 637 millimicrons.

COMPARATIVE EXAMPLE 1

A. To approximately 1.0 liter of distilled water adjusted to a pH in therange of 8.0 to 8.5 with dilute sodium hydroxide solution, there wasadded 3.7 ml of a solution of 1.0 g of FD&C Blue No. 1 dissolved in 1.0liter of distilled water. To the resultant dyestuff solution 4.0 ml of asolution consisting of 10.0 g of a surface active agent (Emulphogene®TB-970, GAF Corp.) and 10.0 g of sodium sulfate dissolved in 1.0 literof distilled water was added.

B. The visible spectrum of a sample of the solution from Part A abovewas recorded with a Perkin-Elmer Lambda® 5 UV/VIS Spectrophotometer. Tothe solution from Part A above, 2.0 ml of a solution consisting of 1.0ml of 5.0 percent active sodium hypochlorite dissolved in 9.0 ml ofdistilled water was added and immediately after a brief mixing, thevisible spectrum of a sample of the mixed solutions was recorded withthe spectrophotometer. Subsequent readings were taken and recordedautomatically by the instrument at several time intervals as indicatedin Table I hereinbelow. The spectrophotometer readings were obtained asthe absorbance of the major wavelength of the dyestuff solution. Thesereadings were converted for ease of communication to percentages bydividing the absorbance obtained at the time intervals after theaddition of the sodium hypochlorite solution by the absorbance of thedyestuff solution obtained prior to the addition of the sodiumhypochlorite solution. The percentages of dyetuff remaining areindicated in Table I hereinbelow. This procedure was used also in thesubsequent tables.

                  TABLE I                                                         ______________________________________                                        FD&C Blue No. 1                                                                            Percent Color Remaining                                          Elapsed Time in Presence of Sodium                                            (Minutes)    Hypochlorite                                                     ______________________________________                                         0           100.0                                                             2           99.5                                                              4           96.0                                                              64          71.0                                                             124          47.0                                                             184          25.0                                                             244          11.0                                                             304           3.0                                                             ______________________________________                                    

C. To a second solution prepared in a manner similar to that describedin Part A above, 11.0 ml of a solution consisting of 1.0 g of 88 percentactive trichloroisocyanuric acid dissolved in 1.0 liter of distilledwater was added and the visible spectrum of a sample was recorded asdescribed in Part B above as indicated in Table II hereinbelow.

                  TABLE II                                                        ______________________________________                                        FD&C Blue No. 1                                                                            Percent Color Remaining                                          Elapsed Time in Presence of                                                   (Minutes)    Trichloroisocyanuric Acid                                        ______________________________________                                         0           100.0                                                             4           84.0                                                             14           49.0                                                             24           32.0                                                             34           26.0                                                             44           23.0                                                             54           22.2                                                             64           22.2                                                             74           22.2                                                             84           22.2                                                             ______________________________________                                    

The shade of the solution slowly shifted toward the red end of thevisible spectrum.

COMPARATIVE EXAMPLE 2

Following the procedure described in Part A of Comparative Example 1, adyestuff solution was prepared substituting 1.5 ml of a solutioncontaining 1.0 g of FD&C Green No. 3 dissolved in 1.0 liter of distilledwater adjusted to pH 8.0 to 8.5 using a dilute solution of sodiumhydroxide for the solution of FD&C Blue No. 1. Parts B and C ofComparative Example 1 were repeated using the FD&C Green No. 3 solution.The test results are indicated in Tables III and IV hereinbelow.

                  TABLE III                                                       ______________________________________                                        FD&C Green No. 3                                                                           Percent Color Remaining                                          Elapsed Time in Presence of Sodium                                            (Minutes)    Hypochlorite                                                     ______________________________________                                         0           100.0                                                             2           100.0                                                             62          61.0                                                             122          31.0                                                             182          12.0                                                             ______________________________________                                    

                  TABLE IV                                                        ______________________________________                                        FD&C Green No. 3                                                                           Percent Color Remaining                                          Elapsed Time in Presence of                                                   (Minutes)    Trichloroisocyanuric Acid                                        ______________________________________                                         0           100.0                                                             2           88.0                                                             12           46.0                                                             22           35.0                                                             32           29.0                                                             42           24.0                                                             52           22.0                                                             62           19.0                                                             ______________________________________                                    

No significant change in the shade of the solution was observed in thepresence of sodium hypochlorite while the shade of the solution wasobserved to undergo a moderate shift to the red end of the spectrumafter twelve minutes in the presence of trichloroisocyanuric acid.

EXAMPLE 1

The procedure described in the Comparative Example 1, Part A wasfollowed except that the FD&C Blue No. 1 solution was replaced by 7.4 mlof a solution containing 1.0 g of the dyestuff prepared in PreparativeExample I above dissolved in 1.0 liter of distilled water which had beenadjusted to pH 8.0 to 8.5 using a dilute solution of sodium hydroxide.

Parts B and C of the Comparative Example 1 employing sodium hypochloriteand trichloroisocyanuric acid, respectively, were repeated with theabove solution with the test results indicated in Tables V and VIhereinbelow.

                  TABLE V                                                         ______________________________________                                        Dye from Preparative Example I                                                             Percent Color Remaining                                          Elapsed Time in Presence of                                                   (Minutes)    Sodium Hypochlorite                                              ______________________________________                                         0           100.0                                                             2           99.0                                                              62          85.0                                                             122          74.0                                                             182          64.0                                                             242          55.0                                                             302          48.0                                                             362          43.0                                                             422          41.0                                                             482          42.0                                                             ______________________________________                                    

                  TABLE VI                                                        ______________________________________                                        Dye from Preparative Example I                                                             Percent Color Remaining                                          Elapsed Time in Presence of Sodium                                            (Minutes)    Trichloroisocyanuric Acid                                        ______________________________________                                         0           100.0                                                            18           70.0                                                             19           69.0                                                             34           58.0                                                             49           50.0                                                             64           44.0                                                             79           39.0                                                             94           36.0                                                             109          32.0                                                             124          30.0                                                             139          28.0                                                             154          26.0                                                             169          25.0                                                             184          24.0                                                             ______________________________________                                    

There was no shift in the shade of the dyestuff solution. After a periodof about five hours, approximately 16 times more dyestuff fromPreparative Example I remained in the sodium hypochlorite sanitizingsolution than the dyestuff identified as FD&C Blue No. 1. After a periodof about one hour, 2 times more of the dyestuff from Preparative ExampleI remained in the trichloroisocyanuric acid sanitizing solution than thedyestuff identified as FD&C Blue No. 1.

EXAMPLE 2

Following the procedure described in Comparative Example 1, Part Aabove, a dyestuff solution was prepared using 6.0 ml of a solutioncontaining 1.0 g of the dyestuff prepared in Preparative Example IIabove dissolved in 1.0 liter of distilled water adjusted to pH 8.0 to8.5 using a dilute solution of sodium hydroxide in place of the FD&CBlue No. 1 solution.

Parts B and C of Comparative Example 1 employing sodium hypochlorite andtrichloroisocyanuric acid, respectively, above were repeated using thesolution prepared above. The test results are given in Tables VII andVIII hereinbelow.

                  TABLE VII                                                       ______________________________________                                        Dye from Preparative Example II                                                            Percent Color Remaining                                          Elapsed Time in Presence of                                                   (Minutes)    Sodium Hypochlorite                                              ______________________________________                                         0           100.0                                                             2           96.0                                                              62          86.0                                                             122          84.0                                                             182          83.0                                                             242          83.0                                                             302          83.0                                                             362          83.0                                                             ______________________________________                                    

                  TABLE VIII                                                      ______________________________________                                        Dye from Preparative Example II                                                            Percent Color Remaining                                          Elapsed Time in Presence of                                                   (Minutes)    Trichloroisocyanuric Acid                                        ______________________________________                                         0           100.0                                                             2           78.0                                                              47          73.0                                                              92          73.0                                                             137          73.0                                                             182          73.0                                                             227          73.0                                                             272          74.0                                                             317          74.0                                                             362          74.0                                                             ______________________________________                                    

No change in the shade of the solution observed in the presence ofhypochlorite. After a period of about five hours, approximately 27.6times more dyestuff identified as Preparative Example II remained in thesodium hypochlorite sanitizing solution than the dyestuff identified asFD&C Blue No. 1. After a period of about one hour, approximately 3.3times more dyestuff identified in Preparative Example II remained intrichloroisocyanuric acid sanitizing solution than the dyestuffidentified as FD&C Blue No. 1.

EXAMPLE 3

A dual compartment automatic dispensing sanitizer for tank and bowltoilets was prepared as follows. A dye-surfactant cake was prepared byheating together 2.0 g of the dye from Preparative Example I having theformula ##STR9## 33.0 g of anhydrous sodium sulfate, and 33.0 g ofEmulphogene® TB-970 (GAF Corp.), a commercialtridecyloxypoly(ethyleneoxy)ethanol surfactant, to form a uniformmixture. The molten mixture was placed into a form and cooled to obtaina solid cake. The cake was inserted into one compartment and a cakecontaining a trichloroisocyanurate sanitizing agent was placed in thesecond compartment. Then the assembled dispenser was placed into thetank of a conventional tank and bowl flush toilet. After severalflushing cycles, the sanitizing solution remaining in the bowl when theflushing cycle was completed remained blue until the next flush. Thetime between flushes varied from several minutes to over six hours. Asimilar dual compartment automatic dispensing sanitizer for tank andbowl toilets was prepared substituting the dyestuff FD&C Blue No. 1 forthe dyestuff indicated above. The blue color in the sanitizing solutionremaining in the bowl when the flushing cycle was completed, faded morerapidly than the dyestuff from Preparative Example I and after sixhours, the solution was colorless.

We claim:
 1. A triphenylmethane compound having the structural formula##STR10## in which: M represents an alkali metal cation, an ammonium ionor an alkaline earth metal cation; andX represents hydrogen or hydroxy.2. A triphenylmethane compound according to claim 1 wherein X ishydrogen.
 3. A triphenylmethane compound according to claim 1 wherein Xis hydroxy.